A long-awaited report on a large and possibly still ongoing outbreak of MERS coronavirus in Saudi Arabia reveals the virus spreads easily within hospitals, at one point passing in a person-to-person chain that encompassed at least five generations of spread.

The study, co-written by Toronto SARS expert Dr. Allison McGeer, also hints there may have been a superspreader in this outbreak, with one person infecting at least seven others.

The study lays out what is known about an outbreak of MERS that erupted this spring in four hospitals in the Eastern Province of Saudi Arabia, in an area whose name translated into English can be spelled Al-Ahsa or Al-Hasa (the study uses the second version). It was reported online on Wednesday by the New England Journal of Medicine.

Superspreaders played a key role amplifying SARS cases during the 2003 outbreak. That, combined with the symptoms patients manifest when they become sick and the long and varied incubation period, paint a picture that is reminiscent of SARS for the authors, several of whom, like McGeer, worked in Toronto to contain that coronavirus.